In the second year after the synthesis of tryparsamide had been accomplished, Pearce and Brown1 noted experimentally that the therapeutic use of the drug was not associated with organic or functional disturbance and, further, that "a definite effect was produced upon the course of the Treponema infection due to the peculiar manner in which the drug modified or controlled the infection." In 1924 these investigators2 further characterized tryparsamide as having "comparative freedom of untoward effect, moderate treponemacidal action, high tissue penetrability, and the ability to reinforce the powers of natural resistance." Tryparsamide is firmly established as an essential modern agent in the therapy of neurosyphilis, and at least certain of these early noted factors have been substantiated by the clinical experience of the intervening period. With regard to the visual aspects of tryparsamide therapy, however, there has been a persistent lack of accord in opinion. When Lorenz and